Universal carriage return mechanism for typewriters



Sept. 17, 1940. F. w. LE FORIN 2, 0

UNIVERSAL CARRIAGE RETURN MECHANISM FOR TYPEWRITEHS Filed May 8, 1937 4 Sheets-Sheet 1 Sept. 17, 1940. F. w. LE PORIN 2,214,906

- UNIVERSAL CARfiiAGE RETURNYMECHANISM FOR TYPEWR IIERS Filed May sj 1957 4 Sheets-Sheet 2 QP F. w. LE PORIN 2,214,906

INVENTOR. FREDE'R/ mz-e FOR/N Sept. 17, 1940. w LE PQRIN 2,214,906

UNIVERSAL CARRIAGE RETURN MECHANISM FOR TYP EWRiTERS Filed May 8, 1937 4 Sheets-Sheet 4 INVENTOR. FEEDER/J W. A: Po/w/v Patented Sept. 17,1940

UNITED STATES PATENT OFFICE UNIVERSAL CARRIAGE RETURN MECHA- NISM FOB TYPEWBITERS Frederic W. Le Porin, Brooklyn, N. Y, assignorto Tykar Corporation, New York, N. Y., a corporation oi New York Application May 8, 1937, Serial No.141,409

13Claims.

to a position adjacent a tabulating stop for tabulating work, and to retum it to a position determined at will.

The automatic carriage return mechanism can be applied to typewriters oi the kinds in general use (in which the carriages are manually returned) with virtually no alteration oi the mechanism of the typewriter, with a minimum of additive parts, and with no alteration of the normal functioning of the typewriter, the automatic return mechanism functioning collaterally or alternatively with the manual return operation.

The invention further provides an improved mechanism which can be economically built, and the parts of which may be assembled with a minimum of special fitting.

The invention further provides an improved mechanism which will operate satisfactorily notwithstanding moderate deformations of the parts due to rough treatment of the typewriter, inaccuracies of alinement, etc., in assembling the parts, and in attaching the mechanism to a typewriter, and in which the construction is such as to eliminate any binding or drag on the carriage during typing.

The invention also provides an improved mechanism which operates easily, without violent shocks, and in which the operation 01' the elements, following the operation 01' a key to start the carriage return and the operation of mecha- 4o nism for stopping the carriage return, is instantaneous and timed so as to obtain the best coaction and in which the stopping of the motor is automatic, following the depression of the automatic full-return key-lever, when the carriage reaches the line-beginning position determined by the marginal stop.

The invention further provides ncveland useful combinations and sub-combinations hereinalter set forth and defined in the claims.

1 An embodiment of'the invention is illustrated in the accompanying drawings, wherein:

Fig. l isa view in side elevation of the carriage return mechanism, with parts of the typewriter shownin dotted lines.

Fig. 2 is a top plan view with parts of the typewriter shown in dotted lines. v

Fig. 3 is an enlarged view in side elevation of parts of the carriage return mechanism (including the motor, speed-reduction gearing, clutch.

. ao key-levers, and switch-and-clutch control-bar) the parts being shown in the position in which the motor is cut ofi and also in the position in which they are when the typing mechanism is being used. I

Fig. 4 is a horizontal sectional view on the line I IV-IV, Fig. 3, showing the switch and omitting the motor.

Fig. 5 is a view similar to Fig. 3, confined to' the parts at the right-hand side, and showing the automatic full-return key-lever depressed and the parts in the position in which they remain during the automatic'return of the typewriter carriage to the marginal-stopping position.

Fig.-6 is a view similar to Fig. 5 (with more parts omitted) showing the automatic limitedreturn key-lever depressed and the parts in the position which they occupy while said automatic limited-return key-lever is maintained in the depressed position.

Fig. '7 is a group view of the two key-levers and control-bar detent, the automatic limited-return key-lever being shown in position with relation to the detent, and the automatic full-return keylever displaced from its position co-axial with, in front of, and alongside of the other key-lever.

Figs. 8, 9 and 10 are views of parts mounted on the front parts of the movable carriage and the stationary frame of the typewriter, respectively, which co-act to initiate the stopping of the carriage-return motor, when the carriage has completed its return movement, as determined by the marginal stops of the typewriter, which marginal stops appear in the figures; in which Fig. 8 is a top plan showing the carriage marginal stop approaching the stopping position; Fig; 9 is a similar view showing the carriage marginal stop and coacting parts in the position in which the control-bar has been released from the detent and the motor switch opened and clutch disengaged, and Fig. 10 is a cross section on the line X-X,

' Fig. 9.

Figs. 11, 12 and 13 are perspective views showing certain of the parts in Figs. 8, 9 and 10 in detail.

Fig. 14 is a vertical cross-section through the drum 34, and its support, and through the speedreducing gears and clutch, Fig. 3.

Referring to said drawings, the stationary parts of the typewriter to which the carriage return mechanism is attached, or is to be attached, are indicated by the'reference letter S, and the mov able spring-tensioned carriage by the letter C.

The carriage return mechanism preferably comprises a base 10, which is conveniently formed by stamping from a sheet of metal, and on which most of the parts of the carriage return mecha= nisin may be mounted. As here shown, base i is conveniently a plate provided with punched.

portions I3 and it which are designed to fit be= tween the feet 15 of thetypem'iter and the base thereof, and base 53' may be attached to the typewriter by removing the feet I5, passing the screws I6 of the feet through the holes in the portions 03 and I 4 of the base, and then fastening the screws I6 in the threaded sockets therefor in the frame of the typewriter. In order that the base I may be readilyattached to typewriters having feet I spaced differently apart, the punched portions I3 and I4 may be formed as separate pieces, as shown, and each have a slot -therein through which passes a screw IT by which said portions I3 and I4 are held in adjusted position on the base l0. 4

There are only a few other parts which are required for attachment to the typewriter. One is the bracket I8 shown in Figs. 2 and 3, which is attached to the typewriter by removing the screw I9 which fastens the top-plate of the typewriter to one of the vertical posts of the typewriter frame, passing the screw I9 through the hole provided therefor in the bracket I8, and then replacing the screw I9. Another part is a small plate 22 (Fig. .13) provided with a beveled face or cam 23, which plate 22 is formed on or fastened to the adjustable marginal stop 24, which latter is carried by the carriage C, and,co-acts with a part 26 pivotally mounted on the typewriter frame S, as indicated at 21.

The part 26 may be, as shown in Fig. 11, a bail-like lever spanning and pivoted on the same block 28 on the frame S as the regular marginal stop 29 is pivoted.

Mounted on the base I0 is an electric motor 30, and adjacent the motor is the frame 32 of aspeed-reduction gearing 33, also mounted on the said base I0. Numeral 34 designates a drum which is connected with the speed-reduction gearing 33 through a universal coupling 36, and which drum 34 has attached thereto a flexible cord or tape 38' which is attached to the movable carriage C, and preferably to the lever L of the line-spacing mechanism on the carriage, the tape at the side of the typewriter passing over a roller 40 which is mounted on the bracket I8 which is attached to the typewriter frame.

The motor drives the drum 34 through a clutch The speed-reduction mechanism 33 advantageously comprises shafts 50 and 5| having meshing helical gears 53, 54 thereon. The helical gears are ,of a type through which motion may be transmitted with equal facility in either direction, and are to be distinguished from worm gears which resist backward turning. The gear 54 turns loosely on a sleeve 55 fixed to the frame 32, and the shaft 5! turns freely in said sleeve 55. The mounting of the gear 54 on the sleeve- 55 has the advantage that any distorting forces acting on the gear 54 are sustained by the sleeve 55, and not by the shaft 5|, and thereby the extremely light running of the shaft 5| when the clutch 44 is disengaged, which is desired, is protected. Also an anti-friction thrust-bearing 51 is provided between the gear 54 and the frame 32, as a means to the same end of obtaining extremelylight running of the shaft 5|, as hereinafter more fully explained.

The axes of shafts 50 and 5| may be arranged parallel to one another, with the shaft 50 in line with the shaft 55 of the electric motor 30,

giving the advantage of a compact and aligned arrangement of the motor 40, reduction gearing 33 and drum 34. To avoid the necessity of accurate alinement between the bearings for shaft 56 and for shaft 50, and to facilitate assem y a universal coupling 58 may be provided between these two shafts. The universal coupling 58 may be similar in construction to the universal coupling 36. These universal couplings have the simple form of adjacent disks coupled through a pin which is fastened to one disk and projects through a slot in the other, as shown. a

The clutch 44, as shown in the embodiment here illustrated, may be combined with the speedreduction gearing 33. The gear 54 may have fixed thereon a jaw-plate BI, and opposite thereto, and

fixed on shaft 5|, is a companion jaw-plate 62.

The shaft 5| is axially movable in its bearing, and such axial movement, to bring the jawsfil and 62 into and out of clutching engagement, is effected through suitable means, as a grooved collar 65 fixed on shaft 5|, and a two-arm shift lever 66, 61, which may be pivoted in a bracket 58, fastened on the frame 32. The shift-lever 66, 51 is acted upon by a spring 1| in a direction to move the shaft 5| axially to bring the jaws 6|, 82 of the clutch into engagement.

Numeral I00 designates a switch for controlling the fiow of current to the motor 30. This switch I00 is conveniently located within a housing forming a part of the frame 32, as shown in Fig. 4. The switch comprises a fixed contact IOI and a movable contact I02. The movable contact I02 is carried on a spring-arm I03. Opposite the spring-arm I03 is arranged a pin or projection I04 which flexes the arm I03 to break the circuit when the arm I03 is moved against said pin. The position of the pin I04 with respect to the spring-arm I03 may be made adJustable as by means of a screw-thread connection I0'I between it and the frame 32. The'switch I00 may be mounted on a plate I05, which is piv-Q .plate has an arm I08 having a projection I09 for a purpose hereinafter explained. The plate I05 carrying the switch I00 is acted on by a spring II I in a direction to bring the arm I03, on which the contactl02 is mounted, into contact with the pin I04, to thereby separate the contacts IOI, I02, to break the circuit to the motor-30. The spring III is conveniently attached at one end to the arm I08 of the plate I05, and at its other end to a part fixed on the frame 32.

The position of the projection I04 may be adjusted so that the making and breaking of the circuit to the motor 30 may be timed with relation to the engagement of the jaws of clutch 44. The preferred timing is such that the clutch 44 is partially engaged before the motor begins to turn shaft 50, and the circuit to the motor 30 broken before or during the disengagement of the clutch 44. I

The drum 34 is conveniently mounted on a stud H6 (Fig. 14) fastened upon a bracket 8, fastened to the frame 32. A ball bearing I20 is preferably provided between the drum 34 and its support, so that the said drum may turn easily under the pull of the tape 38 during the movement of the carriage C, as in typing.

The drum 34 is also preferably acted upon by.

a coiled spring I30 (Fig. 5), one end of which is connected to a flange on the drum, as indicated to turn the drum 34 in a direction to maintain a slight tension or pull on the tape 30, so that .the pull of the spring I 30 on the drum will maintain tautness of the tape 38 throughout all movements of the carriage which occur when the motor 80 is not acting through the drum to eifect the return of the carriage.

The tooth on stud II8 is'so formed as to release the end of spring I38 when the drum 84 is rotated rapidly backward, such as occurs when tape 88 breaks, and such a construction has been found to have the advantage of preventing the breaking of spring I30 in such a contingency.

As a part of the means for controlling the operation of the motor 50, a control-bar I50 is provided. This bar is conveniently in the form of a flat strip extending parallel with the axes of the motor and shafts of the reduction-gears,- and having limited reciprocatory movement. The bar I50 may be supported in brackets I52, I58 attached to the base I of the attachment, the brackets I52, I53 being provided with headed pins I55 which pass through elongated slots I51 in the said bar I50. The bar I50 has therein an elongated notch I80, within which the projection I09 on the arm I08 of the switch I00 extends. The bar I50 also has thereon a pin I82 which extends across thev arm 81, as shown in Figs. 3, 4, and 6. The bar I58 also has thereon a pin I04 (Figs. 1-6) which is adapted to be engaged by a detent I88 which may be pivotally mounted on the bracket 'II8, as indicated at I81. The bar I58 also has thereon two other pins l89and I10.

Numerals I15 and I18 designate key-levers. The key-lever I 15 is designated herein as the automatic full-return key-lever, and the keylever I18 as the automatic limited-return keylever.

The automatic full-return key-lever I15 has thereon a pivoted pawl I12 which coacts with the pin I on the bar I50, and the automatic limited-return'key-lever I18 coacts with the pin I89 on said bar I50, as will be hereinafter more fully explained.

The bar I50 is acted on by a predominant spring I80, and the action of the spring is to normally hold the bar in the position shown in Figs. 3 and 4 where the movement of the bar I50 in the direction of the pull of spring I00 is limited by a shoulder I82 bearing against a stop Ill. The stop I8I is advantageously made adjustable,

as indicated at I88, so that the roller on arm 88' ofthe clutch shift lever is held in a neutral position in the grooved collar 85. The neutral position is one where the clutch parts ii, 82 are fully disengaged and neither the bar I50 nor the spring II acts on the shift-lever 88, 81 in such a way that axially directed pressure is produced by any part on shaft 5I against any fixed part. and the light running of shaft 5i, hereinbefore referred to, is preserved. The pin I82 on the bar I50 bears on the arm 81 of the clutch shift-lever, normally holding the clutch parts 8i and .02 in their disengaged position and the clutch-lever in the neutral position just described. The notch I80 in the bar I 50 also normally frees the projection I 05, so that the. spring III can act to'turn arm ill to hold the switch I00 in position to break the circuit to the motor through the action of projection I04 on spring arm I05 which carries contact I02. The pin I84 on the bar I50 normally lies above the detent I88, and holds it depressed. When the pin I84 on the bar I50 tent I88 is thereafter moved to disengage the pin I84, the force of the predominant spring I80 is such as to overcome the force of the spring 1| acting on the shift-lever 88, 81 of the clutch, andshoot the bar I58 to the position shown in Figs. 8 and 4, as hereinafter described.

The function of the predominant spring I00 is advantageously performed by two springs, one (I80) attached to the'bar on one side, and another, I80, attached to bar I50 on the opposite side. In this way, side thrust of the bar I50 against its supports is avoided, and the possibility of a stifi action or binding avoided.

The automatic full-return key-lever I15 is pivoted as indicated at I83 (Figs. 3, 5, 6 and 7) to the bracket II8. A spring I88 attached at one end to the automatic full-return key-lever I 15 and at its other end to an arm I81 on said frame 02 normally acts to hold said automatic full-return key-lever up, as indicated in Fig. 3.

I91 on the key-lever extending into a slot I98 in the pawl. The pivotal mounting of the pawl I12 and the shape of the tooth of the pawl enable the pawl to slip quickly out of engagement with the pin I10 after the bar I50 has been advanced to a position where the detent I88 is able to rise and engage the pin I84. A spring I98 acts on said detent I88 in a direction to turn it to a position to engage the pin I84. The pin I84 may be mounted on a plate 200 which'is adjustable with respect to the bar I50, so that the proper timing of the engagement ofthe pin I84 by the detent I88 following the release of the 7 pin I10 on the bar I50 by the pawl I12 on the automatic full-return key-lever I15, may be effected.

The automatic limited-return key-lever I18 is pivoted co-axially with key-lever I15, as indicated at I83, and has a portion 20I, which makes contact with pin, I89 on the bar I50, when the said key-lever I18 is depressed. The keylever I18 also has thereon a projection 202 which I (whenthe key-lever I18 is depressed) makes contact with the detent I88 during the movement of bar I50 by the portion 20I of key-lever I18,

and before the pin I84 on the bar I 50 releases.

A clear said key-lever I15 when the key-lever I18 is depressed. A spring 208 attached to arm I81 pulls on key-lever I18 in a direction to hold it up, as indicated in Fig. 3, and the movement of key-lever I18 around its pivot is limited by the abutments I89, |90,-and a projection 204 on said key-lever, Fig. 6.

Suitable means for moving the detent I84 to .release the bar I 50, following the depression of the automatic full-return key-lever I15, as the carriage reaches the end of its return movement against the marginal stop, and thereby stop the operation of the carriage re urn mechanism, are provided. Means suited to the style of typewriter having a marginal stop at the front of the frame, may be as follows and is illustrated in Figs. 1, 2 and 8-13 inclusive: Pivoted on the bracket I8, as indicated at 208, Fig. 1, is a lever 201, and ooacting with said lever 201 is a lever 208 also pivoted to said bracket I8, as indicated at 209, Figs. 2 and 8. The detent I66 has thereon a pin 2H which is adapted to be engaged by the end of said lever 201. A spring 2I3, Fig. 1, connected to said lever 201 and to an arm 255 on said bracket I8 normally tends to hold the lever 201 out of the range of movement of said pin 2H on detent I66. The lower end of said lever 201 is, however, made adjustabla so that the action of saidlever 201 on the detent I66 may be properly timed. The adjustment may be efiected by providing the lever 201 with an extension 220 (Fig. 1) which is pivoted to the lever as indicated at 222, and which ismade fast in its adjusted positions by means of a binding-screw'223.

The lever 208 is held with its end in contact with the pivoted bail-like lever 26 which is pivoted on the frame S co-axial with the marginal 'stop 29. When the adjustable marginal stop 26 carried by the carriage C strikes the roller 235 on the'bail-like lever 26, the said baillike lever 26 is caused to turn rapidly on its pivots. The bail-like lever 26 (being in contact with the lever 208 at its end 230) imparts movement to the said lever 208 around its pivot 209, and the lever 209 acting upon the lever 201, turns this latter lever around its pivot 206, and brings its end against the pin 2I'I on the detent I66, thus moving the detent out of the path of.the pin I64 on bar I50, "and thus allowing the predominant spring I80 to bring the shoulder I82 on bar I against the adjustable stop I8I, in which position, as hereinbefore described, the motor 30 is deenergized and disconnected through the clutch. After the motor 30 is disconnected, the momentum of the carriage C will ordinarily be .suiiicient to carry the carriage the few remaining spaces until the marginal stop 24 abuts against the fixed marginal stop 29, thus bringing the carriage to the line-beginning position.

When the carriage C is in the line beginning position it is advantageous to have the full-return key-lever I15 inefiective to latch the control-bar I50 through the detent I66. The said full-return key-lever I15 is rendered inefiective for the purpose just stated, through the followthe switch I00 cannot be more than momentarily closed.

A means 231 is advantageously provided for adjustably limiting the swing of the bail-like lever 26 toward the marginal stop 24. The means may be, as shown, a stud or pin having a screwthread engagement with the lever 26 and located so as to'come into contact with the top of block 28 as the lever 26 turns toward stop 24. -The contact of stud 231 with block 28 determines the position of rest (or normal position) of bail-like lever 26. In its position of rest, therolle'r 235- should be in such position with relation to the.

nose 239-on stop 24, that when the roller 235 and'nose 239 come into contact, the end of nose 239 will be sufiiciently spaced from the center of the rgller to cause the lever 26 to readily turn land to minimize the shock between the'roller 235 and the nose 239.

Because of the light and easy running'of. the

-68, the mounting of gear 66 on sleeve 55, and the gagemen't with the clutch part 6!. Practically mechanism provided by the non-binding driving connections through the universal joints 36 and anti-friction thrust-bearing 51, the motor 30 may be one of minimum power for doing the work of -:5

returning the carriage. This construction and arrangement, especially when combinedwith the gears (such as the helical gears 53, 56) which transmit motion with equal facility in either direction, has multiple advantages. The shock when the marginal stop 26 on the carriage and the marginal stop 29 come together is mild. The clutch parts SI, 62 may move instantly out of disengagement under the influence of a comparatively light spring. The motor stalls easily when an obstruction is met. by the carriage, damage to the typewriter and injury to persons are avoided, and by reason of the easy reverse turning of the special type of gears which are provided, an object which is caught between the not held but is easily released.-

A cover 250 may be provided for the motor 30 and parts associated therewith on base it).

OPERATION By the use of the two key-levers, the automatic full-return key-lever I15, and the automatic limited-return key-lever I16, the carriage C may be automatically returned from any posi- I tion to any position; i. e. to a position against the marginal stop 29, to a position adjacent a tabulating stop, or to a position determined at the will of the operator. The mechanism functions universally to answer the requirements of automatic carriage-return.

Automatic full-return of carriage, against marginal stop 29 Automatic full-return keyelever n5 is depressed for this purpose. The position of the parts prior to depression of key lever I16 is shown.

in Figs. 3 and8, and the positiomof the parts upon the depression of said key-lever I15 is shown in Fig. 5. When the key-lever I15 is struck, it movesaround its pivot I83, bringing the pawl I12 thereon into contact wih the pin I10 on the bar I50. The pawl I12 moves the bar I50 to the left in Fig. 3, and as the key-lever I15 approaches the limit of its turning movement, the detent I66 rises under the force of its spring I99 to a position behind the pin I64 on the bar' I50. At about the same time the pawl I12 slips off of the pin I10 and reelases thebar I50, after which the bar' I50 is retained by the detent I66. Upon the release of the key-lever I15, its spring I06 restores it to its normal position (shown in Fig. 3) the pawl I12 turning on its pivot I on the return movement of the key-lever so as to pass over the pin I10.

As the bar I60 is projected to the left under the 1 action of the automatic full-return key-lever I15, the edge of slot I60 moves against the projection I09 on the switch-lever008- (Fig. 4), and the pin I62 moves away from the arm 61 of the clutchlever, which allows the shaft 5| to move quickly to the right under the influence of the spring 1|, and thereby bring. the clutch part 62 into ensimultaneously with the movement of the shaft 5|, but with enough time difference to allow the clutch parts to partially engage before the motor 30 starts, the switch I00 is rapidly turned under the influence of the spring pressed bar I50 to v establish the motor circuit through the contacts carriage and a fixed part of the typewriter'is the shaft 50 of the speed reducing means 33 through the universal joint 58. The helical gear 53 drives the helical gear 54, andthe gear 54 being connected to the shaft I through the clutch parts 61, 62 rotates the said' shaft 5|, and the said shaft 5| through the universal joint 36 drives the drum 34. The drum rotates, winding the tape 38 thereon. The winding tape pulls the carriage C until the marginal stop 24 on the carriage is brought to a stop against the mar-. ginal stop 29 (Fig. 2). The tape 38 being connected tothe line-spacing lever L on the carriage, however, first moves the lever L to rotate the platen of the carriage C a distance corresponding to the spacing to be made between lines, and thereafter the pull of the tape 38 on the lever L moves the carriage on its return movement, as just described.

The action of the carriage return mechanism is automatically stopped as follows: As the carrlage returns to within about seven spaces of its limit of movement permited by the marginal stops 24 and 29, the nose 239 of stop 24 (Figs. 9 and strikes the roller on bail-like lever 26 causing lever 26 to turn with great rapidity. The turning movement of the bail-like lever 26 produces a turning movement of the lever 208, and this turning movement of the lever 208 causes a turning movement of the lever 201. The movement of the lower end of lever 201 against the pin 2 on detent I66 moves the detent out of engagement with the pin I64 on the bar I50, and

the bar being thereby released shoots quickly tothe right under the influence of the predominant spring I80; and the movement of the edge of notch I60 (Fig. 3) out of contact with the projection I09 on the arm I08 allows the spring III to turn the switch I00 to move the contacts IOI, I02 apart to quickly break the circuit at the contacts IOI I02, and, at about the same instant, the motor is disengaged through the clutch 44 by the contact of pin I62 with the arm 61 of the clutch lever, turning said clutch lever, and the engagement of the arm 66 of the clutch lever with the collar 65'on shaft 5| slides the shaft 5| to the left, thereby separating the clutch parts 6|, 62. With stop I8I properly adjusted, the clutch lever 66, 61 is held in the neutral position heretofore described, which leaves the shaft 5| extremely free to turn in response to the movement of the carriage during typing. I

The momentum of the carriage C after the stop 24 comes into contact with the roller 235 on the bail-like lever 26'to. initiate the de-energization of the motor, and after the de-energization of the motor, will normally carry the carriage to the limit of its return movement permitted by the marginal stop 29.

Within the range of a" few spaces from the line-beginning position, the limited return keylever I 16 is used for effecting the carriage-return against the marginal stops.

Automatic limited return of carriage Automatic limited-return key-lever I16 is depressed for this purpose. The position of the parts prior to the depression of key-lever I16 is shown in Fig. 3, and the position of the parts upon the depression of said key-lever I16 is shown in Fig. 6. When the key-lever I16 is struck, it moves around its pivot I63, bringing the portion I thereof into contact with the pin I69 on the bar I50, and moves the bar I50 to the position shown in Fig. 6: During the depression movement of the key-lever I16, the arched projection 202 thereon makes contact with the detent I66 before the said detent I 66 is released by the pin I64 on the bar I50, so that the detent I66 cannot rise under the action of its spring I99 (when the aforesaid pin I64 clears the detent) and prevent the return of the bar I50 when the key-lever I16 is released. The arched projection 202 holds the detent I66 depressed, on the return movement of the bar I50, until the pin I64 on the bar I50 passes over the detent I66 so that it cannot rise. That is, the bar I50 remains in its key-lever actuated position (slightly to the left of the position shown in Fig. 6, the depression of the key-lever I16 not being fully'completed) and, when the key-lever 116 is released, the bar I50, under the action of spring I80, follows the return movement of the said key-lever I16. That is, when the key-lever I16 returns to the position shown in Fig. 3, the bar I50 simultaneously returns to the position shown in Fig. 3.

The depression of the said automatic limitedreturn key-lever I16, and the movement thereby of the bar I50, brings about the engagement of the parts 6|, 62 of the clutch 44, and the completion of the circuit to the motor through the energization of the motor 30through the.

switch I00 continues as long as the automatic limited-return key-lever I16 is held in its depressed position. As soon as the key-lever I16 is released, the bar I 50 is simultaneously returned by its spring I80, breaking the circuit to the motor 30 through the switch I00, and moving the parts 6|, 62 of the clutch 44 to disengaging position.

If, for example, the typewriter is being used for tabulation in a column to the right of the linebeginning position determined by the marginal stop '29; the automatic limited return key-lever I16 would be depressed and momentarily held.

-When the tabulating stop on the carriage passes can also be used to advantage in such work as addressing envelopes, where the successive lines of typing are begun at different distances from the margin of an envelope.

The automatic limited return key-lever I16 can also be used to advantage'for successive linespacing when the carriage C is held against a tabulating stop or against the marginal stop 29. In such position, the line-spacing mechanism on the carriage will be operated as many times as the said key-lever I16 is successively struck and released.

The arched construction of the projection 202 on the key-lever I16, clears the key-lever I15 when the former is depressed, so thatthe actuation of the key-lever I16 may be carried on without interference from or movement of the keylever I15.

As the carriage C moves to the left in Fig. 2 in the operation of typing, or as the carriage is shifted back and forth manually,.tension is maintained on the tape 30, soas to avoid slack ocdrum 36, as heretofore described. The tension of the spring 538, however, is not sumciently great to actuate the handle L of the line-spacing mechanism. The drum 3t and shaft 56 being disconnected from the motor through the clutch parts M, 62 at this time, the stop i8! operating to hold the clutch lever 66, 67 in the neutral position heretofore described, and the gear 5 3 bearing on the sleeve 55 instead of on shaft 5!, the said drum 3% turns most freely under the pull of the spring I38 and the pull of the carriage C and offers virtually no resistance thereto.

The character of the gears 53, 54 (described as helical gears) as well as the mounting of gear 54 on the sleeve 55, is of importance to the operation of quickly disengaging the clutch-parts 6i and 52. As the marginal stop 24 on the carriage moves against the marginal stop 29 on the frame,

or as a tabulating stop on the carriage moves against a tabulating stop on the frame, there is a recoil or force produced which is opposite to the driving force of the motor 30. This recoil is transmitted through the drum 34 and shaft 5|, to the clutch parts. The helical gears 53, 5t permit of easy movement in either direction of rotation.

The recoil acting on gear 54 tends to produce movement of the gears 53, 54 in an opposite direction to the direction in which they are driven by the motor and this is transmitted to the armature causing it to move in the opposite direction, and therefore instead of the clutch and gear parts being jammed together by the force of recoil, the clutch-parts are free to 'move away from one another, because the force of recoil can act on the armature of the motor through the helical gears 53, 54 and relieve the pressure on the clutch teeth, and when the pressure on the-clutch teeth is so relieved the clutch parts move apart easily and instantly under the action of the spring I80.

The invention may receive other embodiments than that herein specifically illustrated and de-' scribed.

ing and opening said switch comprising a springtensioned movable part I50, a full-return keylever acting, when depressed, to move said springtensioned part to close said switch, a detent for retaining said spring-tensioned part in switchclosing position, when said full-return key-lever is released, carriage-controlled means for moving said detent to release said spring-tensioned part to open said switch and stop the motor when the typewriter carriage has been returned to a predetermined position, and a limited-return keylever acting, when depressed, to move said springtensioned part to close saidswitch, and having a means for preventing said detent from acting to retain said spring-tensioned part in switch-closing position until said limited-return key-lever is released. I I i 2. Carriagereturn mechanism for typewriters according to claim 1, wherein said means for operatively connecting the motor to the typewriter carriage comprises a clutch; and further comprising means for operating said clutchhaving an operative connection with said spring-tensioned movable part.

3. Carriage return mechanism for typewriters comprising an electric motor; means for operatively connecting the motor to the carriage of .a typewriter; means for starting and stopping the motor comprising a switch; and means for closing and opening said switch comprising a reciprocatory spring-tensioned bar, a, full-return key-lever acting, when depressed, to move said bar to close said switch, a detent for retaining said spring-=tensioned bar in switch-closing position when said full-return key-dever is re= leased, carriage-controlled means for moving said detent to release said spring-tensioned bar to open said switch to stop the motor when the typewriter carriage has been returned to a predetermined position, and a limited-return key-lever acting, when depressed, to move said spring-tem sioned bar to close said switch, and having a means for preventing said detent from acting to retain said spring-tensioned part in switch-closing position until said limited-return key-lever is released.

4. Carriage return mechanism for typewriters according to claim 3, wherein said spring-tensioned bar has pins or projections thereon with which said key-levers contact, said detent being positioned adjacent said key-levers, and wherein said means for preventing said detent from acting to retain said spring tensioned part comprises a part on said limited-return key-lever for contacting with said detent when said key-lever is depressed. 1

5. Carriage return mechanism for typewriters according to claim 3, wherein said spring-tensioned bar has pins or projections thereon with which said key-levers contact, said detent being positioned adjacent said key-levers, and wherein said means for preventing said detent from acting to retain said spring-tensioned part comprises an arched projection on said limited-return keylever which passes around said full-return keylever and is arranged to contact with said detent when said limited-return key-lever is depressed.

6. Carriage return mechanism for typewriters,

comprising an electric motor; means for starting and stopping the motor comprising a switch, means for connecting the 'motor to the carriage of a typewriter comprising a clutch, helical speedreducing gears of a character to transmit motion in reverse directions, a drum, and a flexible connection between the drum and typewriter carriage; and means for closing and opening said switch and said clutch, comprising a spring-tensioned bar, a full-return key-lever acting, when depressed, to move said spring-tensioned' bar to close'said-switch and clutch, a detent for retaining said spring-tensioned bar in switch and clutch closing position when said full-return lever is released, carriage controlled means for moving said detent to release said spring-tensioned bar to open said switch and clutch to stopthe. motor and disconnect it from said drum, when the typewriter carriage has been returned to a predetermined position. and a limited-return key-lever acting, when depressed, to move said spring-tensioned bar to close said switch and clutch,

and having a means for preventing said detent from acting to retain said spring-tensioned part in switch and clutch closing positionv until said limited-return key-lever is released.

7. In carriage return mechanism for typewriters, the combination of an electric motor,

means for connecting the motor to the carriage sioned part to a position in which said shiftlever, in the open-position of the clutch, is held in a neutral position in which no longitudinal pressure is exerted by said shift-lever on said shaft.

8. In carriage return mechanism for typewriters, the, combination of a typewriter carriage, a motor, means for connecting the motor to the typewriter carriage, means for starting the motor comprising a key-lever, a detent for retaining the motor starting means in position to keep the motor running after the release of said key-lever, means for actuating said detent to release said motor starting means comprising a lever on the typewriterframe and a stop or projection on the typewriter carriage, said lever having a cam thereon (roller 235) and said stop having a camcontacting portion which is substantially perpendicular to the line of travel of the carriage, and means for limiting the position of rest of said lever so that the reaction between said stop and cam is moderated and the turning of said lever easily accomplished.

9. In carriage return mechanism for typewriters, the combination of a typewriter frame and carriage, a motor, means for connecting the motor to the typewriter carriage, means for starting the motor comprising a key-lever, a detent for retaining the motor starting means in position to keep the motor running after the release of said key-lever, and means for actuating said detent to release said motor starting means comprising a lever on the typewriter frame and a stop on the" carriage frame, said lever having a cam thereon (roller 235) and said stop on the carriage frame having a cam thereon 23 and a projection 239 in advance of said carriage cam 23, said carriage cam 23 and projection 239 co-acting with said lever cam 235, said carriage projection 239 first making contact with said lever cam 235 to operate and then free the detent, and said carriage cam 23 thereafter, when the carriage reaches the I line-beginning position, co-acting with said lever cam 235 to hold the means for actuating the detent in a position to hold said detent out of action.

10. In carriage return mechanism for typewriters which comprises an electric motor, means for operatively connecting the motor to the carriage of a typewriter, and a switch for starting and stopping the motor, movable means for closing and opening said switch, a detent for holding said switch closing and opening means in switch closing position, a full-return key-lever acting, when momentarily depressed, in conjunction with said detent to move and hold said switch closing and opening means in switch closing position, carriage controlled means for releasing said switch opening and closing means from said detion, and means actuated by said limited-return key-lever for preventing said detent from holding said switch opening and closing means in switchclosing position until said limited-return key lever is released.

11. In carriage return mechanism for typewriters which comprises an electric motor, and means for connecting the motor to the carriage of a typewriter comprising a clutch and speedreducing ears; a shaft on which one of the clutch parts is fastened, and a sleeve providing the hearing for said shaft and within which it is supported on a long bearing and is rota". ale and longitudinally movable, one of said reducing gears having a bearing on the exterior of said sleeve and carrying a companion clutch part, the clutch parts being so arranged as to be brought into and out of clutching engagement by longitudinal movement of said shaft on its bearing in said sleeve.

12. In carriage return mechanism for typewriters which comprises an electric motor, and means for connecting the motor to the carriage of a typewriter comprising a clutch and speed reducing gears; a shaft on which one of the clutch parts is fastened, and a sleeve providing the bearing for said shaft and within which it is supported on a long bearing and is rotatable and longitudinally movable, one of said reducing gears having a bearing on the exterior of said sleeve and carrying a companion clutch part, the clutch parts being so arranged as to be brought into and out of clutching-engagement by longitudinal movement of said shaft on its bearing in said sleeve, and an antifriction thrust-bearing for said speed-reducing gear acting to sustain-thrust in the direction of the closing movement of the clutch.

13. In carriage return mechanism for typewriters which comprises an electric motor, and means for connecting the motor to the carriage of a typewriter comprising a clutch and speedreducing gears; a shaft on which one of the clutch parts is fastened, a sleeve providing the bearing for said shaft and within which it is supported on a long bearing and is rotatable and longitudinally movable, one of said reducing gears having a bearing on the exterior of said sleeve and carrying a companion clutch part, means for moving said shaft longitudinally on its bearing in said sleeve comprising two oppositely acting springs, one spring acting on said shaft in the direction of the closing movement of the clutch, and the other spring'being predominant and acting on said shaft in the direction of the opening movement of the clutch, and means for manually relieving said shaft of the'action of said predominant spring, thereby allowing said spring which acts in the direction of the closing movement of the clutch, to move the clutch parts into clutchengagement, said sleeve bearing providing a true hearing which enables the shaft to slide longitudinally with only the slight friction of the bearing to oppose its movement.

FREDERIC W. LE PORIN. 

